Func::new_polymorphic

lib/runtime-core/src/loader.rs

@@ -1,7 +1,9 @@
 //! The loader module functions are used to load an instance.
 use crate::{backend::RunnableModule, module::ModuleInfo, types::Type, types::Value, vm::Ctx};
 #[cfg(unix)]
-use libc::{mmap, mprotect, munmap, MAP_ANON, MAP_PRIVATE, PROT_EXEC, PROT_READ, PROT_WRITE};
+use libc::{
+    mmap, mprotect, munmap, MAP_ANON, MAP_NORESERVE, MAP_PRIVATE, PROT_EXEC, PROT_READ, PROT_WRITE,
+};
 use std::{
     fmt::Debug,
     ops::{Deref, DerefMut},
@@ -169,7 +171,7 @@ impl CodeMemory {
                 std::ptr::null_mut(),
                 size,
                 PROT_READ | PROT_WRITE,
-                MAP_PRIVATE | MAP_ANON,
+                MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
                 -1,
                 0,
             )
@@ -196,6 +198,20 @@ impl CodeMemory {
             panic!("cannot set code memory to writable");
         }
     }
+
+    /// Makes this code memory both writable and executable.
+    ///
+    /// Avoid using this if a combination `make_executable` and `make_writable` can be used.
+    pub fn make_writable_executable(&self) {
+        if unsafe { mprotect(self.ptr as _, self.size, PROT_READ | PROT_WRITE | PROT_EXEC) } != 0 {
+            panic!("cannot set code memory to writable and executable");
+        }
+    }
+
+    /// Returns the backing pointer of this code memory.
+    pub fn get_backing_ptr(&self) -> *mut u8 {
+        self.ptr
+    }
 }
 
 #[cfg(unix)]